The present invention relates to antiplaque compositions, and especially to antiplaque chewing gums. Typically, such gums help to fight plaque by mechanically removing it from the teeth. Thus, they incorporate some type of abrasive such as zirconium silicate or the like. It is believed that the only antiplaque chewing gum commercially introduced is one which incorporates an abrasive system.
The F.D.A. categorizes chewing gum as food products. Abrasive ingredients have not been qualified as food ingredients. Hence, a gum containing such an abrasive is an adulterated food which should not be marketable except as a cosmetic or drug. Further, the long range implications of swallowing such abrasive is an unknown. Thus, the use of such abrasives in gum has to be regarded as suspect, notwithstanding the abundant showing of such gums in the patent literature.
Further, such abrasive gum products act to remove plaque only from the abraded areas, i.e., the masticating tooth surfaces. This is inadequate since plaque control is more important on the buccal, lingual and interdental surfaces.
It has long been recognized that some essential oils have some antiplaque activity. Such essential oils have been used in mouthwashes for many years.
In U.S. Pat. No. 4,170,632 issued Oct. 9, 1979 and entitled "PLAQUE INHIBITING COMPOSITIONS AND METHOD," Wagenknecht et al. teaches the use of plaque inhibiting flavor oils, specifically cinnamon, peppermint and spearmint oil in conjunction with zinc compounds in a plaque inhibiting chewing gum. U.S. Pat. No. 4,242,323 discloses a plaque inhibiting oral composition, including in one embodiment a chewing gum, comprising cocoa powder and plaque inhibiting amounts of peppermint oil, spearmint oil and/or cinnamon oil. The use of abrasives or polishing agents is also suggested.
The particular essential oils used in these two proposed gums, neither of which is believed to have been sold commercially, are flavorful and are commonly used as flavor oils. Unfortunately, they are not strongly antimicrobial and hence not exceptionally effective against plaque. The more effective antiplaque essential oils, on the other hand, do not taste very good. For example, mouthwash products incorporating the more effective antimicrobial essential oils are widely recognized to have an undesirable flavor.
Finally, many of the naturally occurring essential oils are in fact mixtures, rather than being chemically specific. Their actual composition will vary from source to source and season to season. Hence, mixture oils such as peppermint oil, spearmint oil or cinnamon oil may be more plaque effective in one season or from one source than another. This creates an unacceptable quality control problem.